1. Field of the Invention
The present invention is directed toward nanowires capable of contacting individual cells, and methods of using the same. The nanowires according to the present invention can effectively and efficiently manipulate single cells and/or sense forces exerted by single cells. These nanowires may be used in a number of applications including, but not limited to, single cell or subcellular contact force sensing, and excision and/or transplantation of single cell to few cellular level tissues.
2. Description of the Prior Art
Several diverse biomedical fields would benefit from devices that can manipulate and/or sense various characteristics of individual cells. Manipulation and sensing various characteristics of individual cells requires devices comparable in size to the cells of interest. For example, detecting the adhesive contact forces exerted by a cell's pseudopod appendage on a substrate requires a sensor comparable in size to this contact site. Despite the importance of pseudopod-substrate adhesive contacts in force transmission and environmental sensing, which influences the direction of migration of leukocytes or breast cancer cells, there have been few measurements and little characterization of pseudopod-substrate adhesive contacts at the single-contact level.
One current technique used for measuring cellular contact forces is the deformable substrate method, which involves observation of cell induced wrinkling or marker displacement of an elastic substrate. However, with this method, the forces at the discrete single adhesive contact sites are not directly measured. Instead, these forces are extracted by a non-trivial modeling effort that correlates the substrate displacement field with the inferred force field and with the discrete contact sites. Another current technique employs the use of an atomic force microscope (AFM) to measure cellular contact forces. However, conventional AFM cantilevers are too bulky to be precisely interfaced with such amorphous and dynamic submicron-sized targets and, as a result, have difficulty measuring the forces exerted by single pseudopod substrate adhesive contacts.
Additionally, in other medical fields, there is an absence of devices that can manipulate individual cells. For example, in certain instances, it is beneficial to excise and/or transplant tissue samples at the cellular level. However, conventional scalpels and curettes are too large and bulky to remove surrounding tissue and cells in such procedures. Therefore, there is a need for devices that can effectively and safely manipulate individual cells and/or sense various characteristics of individual cells.